Gunshot detection and localization based on Non-negative Matrix Factorization and SRP-hat

This paper describes a sound source detection and localization system where the sound source is a gunshot. The proposed system is composed of two consecutive stages: detection and localization. In this manner, the localization system is activated when a gunshot is detected. The detection stage is based on a Non-negative Matrix Factorization (NMF) approach. The localization stage proposes a modification of the method called Steered Response Power Phase transform (SRP-Phat). Firstly, we estimate the delay between multichannel signals that are captured by a six microphone array. Generalized Cross-Correlation (GCC), Generalized Cross-Correlation Phase transform (GCC-Phat), Steered Response Power Phase transform (SRP-Phat) and the proposed localization method are compared. Evaluation indicates that the proposed detection and localization method provides promising results in many acoustic scenarios including noisy environments with low signal-to-noise ratios. The proposed application is designed following the paradigm of smart sound processing and is focused on security needs in a real life scenario.